Adsorption mechanism and property of a novel adsorption material PAM/SiO2 towards 2,4,6-trinitrotoluene.

2,4,6-Trinitrotoluene (TNT) is toxic and mutagenic to many living organisms, so more and more rigorous limits on the letting amount of TNT have been established. In this paper, functional monomer acrylamide (AM) was grafted step by step on the surface of silica gel particles, and the grafted particle PAM/SiO(2) with strong adsorption ability for TNT was formed. The adsorption mechanism and properties of PAM/SiO(2) for TNT were researched through static and dynamic methods. The experimental results showed that PAM/SiO(2) possesses strong adsorption ability for TNT with interaction of three kinds of hydrogen bonds including peculiar NHcdots, three dots, centeredpi hydrogen bond (aromatic hydrogen bond) and CHcdots, three dots, centeredOC pi hydrogen bond. The saturated adsorption amount could reach to 0.873 mg g(-1). The empirical Freundlich isotherm was found to describe well the equilibrium adsorption data. In addition, the pH and temperature were found to have great influence on the adsorption amount. Mixture solution of HCl and ethanol is used as eluent, and the adsorbed TNT is eluted easily from PAM/SiO(2). Finally, PAM/SiO(2) was found to have excellent reusability.